Molecular Thermodynamics of Fluid-Phase Equilibria

Chapter 6 Fugacities in Liquid Mixtures: Excess Functions

Calculation of fugacities from volumetric properties was discussed in Chap. 3; many of the relations derived there [in particular, Eqs. (3-14) and (3-53)] are general and may be applied to condensed phases as well as to the gas phase. However, often it is not practical to do so because the necessary integrations require that volumetric data be available at constant temperature and constant composition over the entire density range from the ideal-gas state (zero density) to the density of the condensed phase, including the two-phase region. It is a tedious task to obtain such data for fluid mixtures and very few data of this type have been reported. A more useful alternate method, therefore, ...